The reason you may be experiencing an oily itchy scalp is your over cleansing it. When the scalp is dry, the sebum glands react to produce more sebum. You could also have pattern hair loss or premature thinning. There are many topical oils that soothe, are anti-inflammatory and help with calming the scalp. Sea Buckthorn is good if you have demodex infestation. There are also oral supplements that help with reducing oil production such as Borage oil. I've been a licensed cosmetologist for the last 25 years, and in the last 4 years, I've been treating thinning hair, hair loss and problem scalp conditions. There is a cutting edge medical office in Davis CA that promotes holistic health. They take a family History, full blood panel and test it against 90 allergens hormonal and chemical imbalances and check filtering organ function. I personally believe since the skin is the largest organ of the body, it is often the barometer of internal health. When positive changes occur internally and cleansing treatments help remove build up, follicle impurities and is supported with organic products and supplemental oils and orals, our skin reacts and gets healthier. That includes the skin and scalp.